Need to revise recommendations for emergency water treatment with bleach in the United States
This presentation is the property of its rightful owner.
Sponsored Links
1 / 13

Need to revise recommendations for emergency water treatment with bleach in the United States PowerPoint PPT Presentation


  • 47 Views
  • Uploaded on
  • Presentation posted in: General

Need to revise recommendations for emergency water treatment with bleach in the United States. Daniele Lantagne, Bobbie Person, Natalie Smith, Ally Mayer, Kelsey Preston, Elizabeth Blanton, Kristen Jellison Centers for Disease Control and Prevention & Lehigh University.

Download Presentation

Need to revise recommendations for emergency water treatment with bleach in the United States

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Need to revise recommendations for emergency water treatment with bleach in the united states

Need to revise recommendations for emergency water treatment with bleach in the United States

Daniele Lantagne, Bobbie Person, Natalie Smith, Ally Mayer, Kelsey Preston, Elizabeth Blanton, Kristen Jellison

Centers for Disease Control and Prevention & Lehigh University


Current epa emergency guidelines

The 3 B’s:Bottled, boil, bleach

If you can't boil water, you can disinfect it using household bleach. Bleach will kill some, but not all, types of disease-causing organisms that may be in the water. If the water is cloudy, filter it through clean cloths or allow it to settle, and draw off the clear water for disinfection. Add 1/8 teaspoon (or 8 drops) of regular, unscented, liquid household bleach for each gallon of water, stir it well and let it stand for 30 minutes before you use it. Store disinfected water in clean containers with covers.

Additionally, in the more information section, the instructions read “double the amount of chlorine for cloudy, murky or colored water or water that is extremely cold.”

Current EPA Emergency Guidelines


Concerns with guidelines technical

Inconsistent dosing: 1/8 teaspoon != 8 drops

High dosage:

1/8 teaspoon (5.25% bleach in 1 gallon): 8.67 mg/L

8 drops (5.25% bleach, 1 gallon, 15-25 drops/mL):4.44 - 5.55 mg/L

EPA maximum: 4 mg/L

WHO maximum: 5 mg/L

Used in HWTS in developing countries:2 mg/L

Double these doses for turbid water

Concerns with guidelines - technical


Concerns with guidelines social

How the recommendations propagate

Whether the items necessary to complete the recommended treatment method are available

Whether people feel confident in completing this water treatment method

1/196 in Hurricane Rita knew correct dose (Ram)

Concerns with guidelines - social


Propagation of recommendations

Propagation of recommendations


Methods

Addressed this in working group

Result: Need data from US

Quantitative

6 states:Colorado, Georgia, Minnesota, Penn, Texas, Wash

6 waters:tap, water heater, surface (filtered & not), wells

Dosage testing at 3 doses, including microbiology and CT-factor

Qualitative

3 states: Louisiana, Florida, Georgia

Stakeholder interviews

Household visits to 9 families with four directions

Observe and test ability to make solution

Methods


Quantitative results water quality 36

6 tap water, 6 water heater, 11 wells, 1 rain barrel

6 surface water (raw, filtration through linen napkin)

pH:mean 7.85 (range: 6.5-9.4)

7/36 exceeded 8.0

Turbidity:mean 3.89 NTU (range: 0-23.2)

18/36 (50%) >1.0 NTU; 4/36 (11%) between 10-100 NTU

Temperature varied geographically and seasonally

E. coli only in surface water (<10–180 CFU/100 mL)

Total Coliforms found in 18/36 samples

Quantitative results - water quality (36)


Quantitative results dosage

Three criteria

FCR >= 0.2 mg/L and <= 4.0 mg/L

E. coli and Total Coliform = 0 CFU/100 mL

Meeting 3-log reduction for Giardia

Quantitative results - Dosage


Quantitative results standard

What criteria are most relevant?

FCR maintenance / FCR guidelines

the inactivation of Giardia in surface waters

the absence of E. coli / Total Coliform

a CT-factor to remove the majority of bacteria and viruses that cause diarrheal disease

a combination of the above?

In any case, current dosages are too high

Quantitative results - Standard?


Qualitative results stakeholder meetings 86

The government should, and does, provide bottled water

A minority knew about bleach for treatment

None knew dosage

All reported serious concerns (Poison Control Center)

Stated instructions are too confusing

“Bleach will kill some, but not all, types of disease-causing organisms.”

“Draw off”

Prefer kit

Laminated instruction, container, pre-measured dose

Qualitative results - Stakeholder meetings (86)


Qualitative results household interviews

Presence of materials

6/9 had bleach in home

None was unscented, non-expired, near 5.25%

1/9 families had a 1/8 teaspoon

2/9 had dropper

4/9 had a gallon container

Methods

Existing (1/8 tsp), existing (8 drops), other dropper, stock solution (WHO)

Dropper method easiest, most accurate, and preferred

Improve by having 2-L container, pictoral directions

Qualitative results - Household interviews


Summary

Based on these results, both quantitative and qualitative, it is recommended that the current recommendations for emergency water treatment with household bleach be reviewed to establish an internally consistent, scientifically verified dosage regime that balances existing regulatory criteria, recommended water sources, population exposure to pathogens of concern, and availability of items (bleach, droppers, measurers, containers) necessary to treat water in the home, including the potential for development of a commercial product for water treatment instead of recommending the use of household bleach.

Summary


Acknowledgements

The stakeholders interviewed

The households who completed the qualitative testing

The households who hosted the testing

Happy to take questions:

[email protected]

Acknowledgements


  • Login